Towards green extraction methods from microalgae learning from the classics

Microalgae are tiny green factories packed with health-boosting compounds—so why are we still using harsh, toxic methods to unlock their treasures?

Microalgae have long been celebrated as a source of third-generation biofuels, but their true wealth lies in a cornucopia of bioactive molecules with proven benefits for human health. These compounds are in high demand, yet extracting them efficiently—without harming the environment or ourselves—remains a challenge. Traditional methods often target a single molecule class and rely on toxic solvents, leaving a heavy ecological footprint. Enter the microalgal biorefinery: a vision where we fractionate the entire biomass into multiple high-value products, maximizing both profit and sustainability. This review charts the journey from classic techniques to cutting-edge green alternatives, including switchable solvents, microwave-assisted extraction, and compressed fluids. The goal is clear: obtain pure compounds while preserving their biological activity, and do it all with minimal environmental impact. By comparing old and new approaches, scientists are rewriting the rules of extraction—turning a necessary step into a sustainable art.

Key Points

• Microalgae offer high-value bioactive compounds for health.
• Green extraction methods reduce environmental and health impacts.
• New techniques preserve bioactivity while improving purity.